Background: Although the concept of workload is important to nursing practice, only a few nursing researchers have focused on the issue of workload within the nursing context. Knowledge of how the dynamics of workload affects the job stress of nurses working in a specific unit or department in a hospital setting, and the influence of coworker support on this relationship, still remains limited. This study, therefore examined the effect of workload on job stress of Ghanaian outpatient department nurses and the moderating effect of coworker support on this relationship. Methods: A cross-sectional survey design was used, and questionnaire was used to collect data from a sample of 216 outpatient department nurses from four major hospitals in Ghana. The data collected measured workload, job stress, and coworker support using National Aeronautics and Space Administration (NASA) Task Load Index, job stress scale, and coworker support scale, respectively. Data were analysed using descriptive statistics, correlation, and hierarchical regression. Results: High levels of workload were associated with high levels of job stress of the nurses. Also, higher levels of workload were related to higher levels of job stress for nurses who received high levels of coworker support, but this was not the case for those who received low levels of coworker support (reserve buffering effect). Conclusion: The finding reiterates the adverse effect of workloads on employees' health, and the reverse buffering effect implies that supporting a colleague at work should be conveyed in a positive manner devoid of negative appraisal. (C) 2019 Occupational Safety and Health Research Institute, Published by Elsevier Korea LLC.
